A new approach to study neurodegeneration in Drosophila

Human neurodegenerative diseases cause devastating clinical symptoms including movement disorders, or cognitive and memory loss due to dysfunction and loss of specific neurons in the brain. These diseases include Parkinson disease, Alzheimer disease, trinucleotide expansion diseases of (polyQ) diseases and noncoding trinucleotide expansion diseases such as Friedreich's ataxia (FRDA).

Drosophila is a good model for neurodegenerative diseases, since has a complex nervous system and displays complex behaviors. In addition, many of its genes are conserved with the ones in mammals.

In our lab we developed assays based on the expression of the neurotoxic agent (i.e. a PQP) in a specific neuronal population on fly's behavior. Most of these strains have aberrant circadian rhythms and the length of the PolyQ correlated with the rhythm defects.Characterizing the strain expressing MJD78Q consists of the C terminus of ataxin 3 with an expanded glutamine tract (78 residues) which is observed in individuals with Machado Joseph Disease (MJD), results with completely arrhythmic behavior and neuronal death (fig1).

Recently, we also established a Drosophila model for another neurodegenerative disease - Friedreich's ataxia (FRDA). We suspect that the fly's behavior will reflect the progress of disease similarly to the progression of the disease in affected individuals.